Oil spills could harm the Arctic more than expected

Technical University of Denmark (DTU) conducted research that revealed that plankton—the foundation of the food chains in the Arctic Ocean—are affected by concentrations of oil pollution much lower than previously assumed. For full article click here.

The Arctic sea ice is melting due to climate change. This creates an increased interest in exploring the oil resources in the area. But how will oil spills from, e.g., oil drilling or tankers affect the Arctic ecosystem?

New research published by DTU Aqua and COWI in the highly respected American journal Environmental Science and Technology shows that an oil spill—in this case in the winter—can have more serious consequences for food chains in the Arctic than previously assumed.

One of the explanations for the new findings is that the researchers exposed the copepods to pyrene for a longer period of time. Previous studies have only lasted a few weeks, but that is insufficient if you want to mimic oil spill conditions.

Like most animals in the Arctic, the copepods hibernate during the long, dark winter. They spend the winters close to the seabed living off their fat deposits, but once the sun boost the growth of phytoplankton in the surface, they swim up to eat the algae and then they grow and reproduce and make up the food basis for the rest of the food chain.

In the laboratory, researchers reproduced the life cycle of the two main copepods in the Arctic—Calanus glacialis and Calanus hyperboreus—and subjected them to different doses of pyrene for three months during the copepod winter break. The pyrene doses used corresponded to actual doses that may occur in an oil spill in nature. The copepods were then transferred to clean water and were fed for a month to imitate the spring phytoplankton bloom.

Calanus glacialis was most affected by the oil spill and did not fully utilize its fat deposits as well as having a higher mortality rate during the winter when exposed to pyrene—and the more pyrene, the greater the effect. Furthermore, researchers recorded negative effects on the copepods’ ability to eat and rebuild fat deposits and produce eggs when they were fed again.

About UArctic

The University of the Arctic (UArctic) is a cooperative network of universities, colleges, and other organizations committed to higher education and research in the North. Our members share resources, facilities, and expertise to build post-secondary education programs that are relevant and accessible to northern students. Our overall goal is to create a strong, sustainable circumpolar region by empowering northerners and northern communities through education and shared knowledge.